Automotive vehicles, and particularly trucks and buses of varying sizes, are commonly used to transport goods, passengers, and for other purposes. In the case of larger vehicles, for example buses and tractor trailers, the driver may have an obstructed view out of the rear of the vehicle, or no rear view at all. For example, in the case of a tractor trailer the trailer blocks the driver's view through the rear view of the cab; in many buses, no rear view window is provided. In these and other vehicles having a limited or obstructed view from the driver's seat through the rear of the vehicle, the side view minors are extremely important for safe and defensive driving.
In order to determine when it is safe to change lanes, and for other driving manoeuvres, the driver of the vehicle must have a clear and unobstructed view to the rear along the sides of the vehicle. This is provided by the side view mirrors. Accordingly, in such large vehicles, for example commercial vehicles such as trucks, motor coaches and heavy equipment trucks (for example dump trucks); and other large vehicles such as recreational vehicles and the like, the side view minors are typically fairly large, and often consist of two parts: an upper part which is a standard planar reflective minor, and a lower part which is a convex or “wide angle” minor allowing the driver a broader field of view rearwardly along the sides of the vehicle.
Because of the position of the driver in the driver's seat, the side view mirrors are mounted immediately adjacent to the side edges of the windshield of the vehicle, typically forwardly of the driver to minimize the degree to which the driver must turn his or her head in order to see the image in the mirror. In this position the mirrors can be angled such that the driver has a full field of view rearwardly along the sides of the vehicle, but without obstructing the driver's forward view out of the windshield of the vehicle.
For safe driving, the windshield needs to be kept clear of water in its various phases (for example falling rain, ice or snow, or accumulated rain, ice or snow sprayed up from the road by a vehicle in front of the large vehicle) and debris (for example grit, stones or other particulate or granular matter) kicked up by a vehicle travelling in front of the large vehicle. This is accomplished by reciprocating windshield wipers, which are pivotally anchored either at the base or at the top of the windshield, and have an elastomeric wiper pressing against the windshield. As the windshield wipers pivot from side to side, the wiper clears the windshield by sweeping water and debris off to the sides of the windshield.
This causes the problem that as the windshield is cleared, the water and/or debris are swept toward the side view mirrors by the windshield wipers. Because of the angle at which each side view mirror must be positioned in order to reflect light from the rear of the vehicle toward the driver's seat, the reflective surface of the minors are exposed to the water and debris being cleared from the windshield by the windshield wipers. The constant bombardment, and potentially accumulation, of water and/or debris on the reflective surface of the minors renders driving unsafe in many circumstances, particularly during heavy rainfalls or snowfalls; or on wet or debris-laden roads where the water and debris are sprayed onto the front of the large vehicle by vehicles driving immediately ahead of the large vehicle.